兔急性脊髓损伤磁共振扩散张量成像参数与血小板活化因子表达的关系

Relationship between diffusion tensor imaging coefficient and expression of platelet activating factor in rabbits with acute spinal cord injury

中文关键词:  急性脊髓损伤  磁共振扩散张量成像  血小板活化因子  模型  兔

英文关键词:Acute spinal cord injury  Diffusion tensor imaging  Platelet activating factor  Model  Rabbit

中文摘要:

  【摘要】 目的：分析磁共振扩散张量成像（diffusion tensor imaging，DTI）的参数表观扩散系数（apparent diffusion coefficient，ADC）值、各向异性分数（fractional anisotropy，FA）值与血小板活化因子（platelet activating factor，PAF）含量的相关性，探讨DTI对急性脊髓损伤的诊断价值。方法：采用12只中国大耳白兔，随机抽取6只作为实验组，另6只作为对照组。实验组切除T10椎板，采用Allen′s打击法制成急性脊髓损伤模型；对照组仅切开背部肌肉，暴露脊膜，不损伤脊髓。两组兔在造模后1d、3d、5d、7d行MRI平扫、DTI扫描，并测定股静脉血及脑脊液PAF含量，用Neuro 3D软件在FA图及ADC图上测量FA值及ADC值，对实验组的FA值及ADC值与PAF含量进行Pearson相关分析。结果：与对照组比较，实验组各时间点ADC值明显升高，FA值明显降低（P＜0.01）。随着时间点的推移，实验组ADC值逐渐升高，FA值逐渐降低（P＜0.01），对照组各时间点ADC值、FA值未见明显变化（P>0.05）。实验组血浆及脑脊液PAF含量较对照组明显增高（P＜0.01）；实验组血浆及脑脊液PAF含量在造模后1d、3d、5d 逐渐升高（P＜0.01），7d 降低（P＜0.01）；对照组各时间点PAF值未见明显变化（P>0.05）。实验组造模后1d、3d、5d血浆及脑脊液PAF值与ADC值呈明显正相关，7d呈负相关（|r|>0.8，P＜0.05）；与FA值1d、3d、5d呈明显负相关，7d呈正相关（|r|>0.8，P＜0.05）。结论：ADC值、FA值与PAF含量具有良好的相关性，DTI参数能反映脊髓继发性损伤的发生和发展过程。

英文摘要:

  【Abstract】 Objectives: To analyze the correlation between the parameters including fractional anisotropy(FA) and apparent diffusion coefficient(ADC) of magnetic resonance diffusion tensor imaging and the content of platelet activating factor(PAF), and to explore the value of DTI in the diagnosis of acute spinal cord injury. Methods: 12 Chinese white rabbits, 6 were randomly selected as experimental group, and the other 6 as control group. Resection of T10 lamina on the experimental group was performed, then the Allen′s method was used to simulate the model of acute spinal cord injury, while the control group was only exposed the spinal cord, and dura mater remained intact. At each time point after modeling, the regular MRI and DTI scans were respectively performed, then the PAF concentrations in cerebrospinal fluid and femoral vein serum were tested. 3D Neuro software was used to measure FA value and ADC value on the FA chart and ADC chart, the FA value and the ADC value of the experimental group were analyzed by Pearson correlation with PAF content. Results: Compared with the control group, the ADC value at each time point significantly increased in the experimental group, the FA value was significantly lower(P<0.01). With the passage of time, the ADC value of the experimental group gradually increased, the FA value gradually decreased(P<0.01), there was no significant change in the control group at each time point(P>0.05). The plasma and cerebrospinal fluid PAF of experimental group were significantly higher than those of the control group(P<0.01), the plasma and cerebrospinal fluid PAF content of experimental group increased at 1d, 3d and 5d(P<0.01), but decreased at 7d(P<0.01), PAF values of the control group showed no significant change at each time point(P>0.05). Serum PAF and cerebrospinal fluid concentrations of the experimental group after modeling were positively correlated with ADC value at 1d, 3d, 5d, negatively correlated with ADC value at 7d(|r|>0.8, P<0.05), and it was negatively correlated with FA value at 1d, 3d, 5d, positively correlated with FA value at 7d(|r|>0.8, P<0.05). Conclusions: FA value and ADC value have a good correlation with PAF; DTI parameters can reflect the occurrence and development of secondary injury of spinal cord.